Metallurgical furnace.



U. WEDGE.

METALLURGICAL FURNACE APPLICATION 3mm) MAY 11 1911 1,086,494, I Patenwd Feb. 10, 1914 ZSHEETS-SHEET l.

' WITNESSES 7 INVENTOR UTLEY 'WEDGE BY HIS'ATTORNEY 7611;, Q'M

U. WEDGE.

METALLURGICAL FURNACE.

APPLICATION FILED MAY 11, 1911.

1,086,494. Patented Feb. 10, 1914 2 SHEETS-SHEET 2.

'TNEssEs INVENTOR 76M 07M T WEDGE BY HIS ATTORNEY &1; w-M

UTLEY WEDGE, OF ARDMQRE, PENNSYLVANIA.

METALLURGICAL FURNACE.

Specification of Letters Patent.

Application filed May 11, 1911.

Patented Feb. '10, 1 914.

Serial No. 626,516.

To all whom 'it may concern:

Be it known that I, UTLEY \VEDGE, a citizen of the United States, and a resident of Ardmore, Pennsylvania, have invented certain Improvements in Metallurgical Furnaces, of which the following is a specification.

My invention relates to that class of.

7 ing had to the accompanying drawings, in

which Figure 1 is a vertical sectional view of a furnace of the superposed hearth type illustrating one application of my invention, and Fig. 2 is a similar section of a like type of furnace illustrating another application of my invention. y

Although my invention is not specifically limited to that type of furnace, I have illustrated it in connection with a furnace having a series of superposed treating hearths 1, and a central shaft 2 provided with projecting arms 3 which are intended to be provided with the usual 'rabbles or blades whereby the material under treatment is fed across each hearth from the outside to the inside or from the inside to the outside of the latter, suitable openings 4 being provided for the passage of the material from each hearth onto the hearth below and for the discharge of the material from the lowermost hearth.

In the furnace shown in Fig. 1 the roof of each treating chamber is hollow so as to provide a chamber 5 to which air is admitted from a vertical flue6 at one side of the furnace this flue having a number of openings 7 through any one or more of which air may be admitted thereto. This air is heated in its passage through the chambers 5 from one side of the furnace to the other, where it enters a flue 9 and from the latter passes through openings 10 into any desired number of treating chambers of the furnace.

- It sometimes happens, however, that the air is not sufliciently heated n its passage through the chambers 5 and in order to increase the heat of the air before it enters the treatin'g'chambers of thefurnace, I 'provide the flue 9 with a number of electric heaters whereby the air maybe thoroughly heated before it enters the treating chambers of the furnace. These heaters may consist of resistance coils 11 carried by insulating blocks 12 inserted through openings in the side wall of the furnace so as to be individually removable laterally, or a series of such resistance coils may be carried by a single insulating block 13 so that the entire series is removable as a unit, or theelectric heating device may consist of a resistance wire or ribbon 14 removable vertically from the flue 9, these electrical resistance devices becoming highly heated when the current is passed through the same and serving to increase the temperature of the air flowing pastthe same in order to insure the heating of the air to the proper temperature before it enters the treating chambers of the furnace.

The flue 9 may be in communication with all of the heating chambers 5, or the said flue 9 may-be closed at intervals by means of blocks or plugs 15, as shown by dotted lines, so that air heated by passage through one of theheating chambers 5 may be directed past the electrical heating devices and caused to enter the treating chamber above or below the same.

The side wall of the furnace may have a number'of openings communicating with the flue 9 and air may be admittedto said flue through any one or'more of these openings, so as to be heated by the electric resistance device inthe flue, such supply or supplies of air being used either independently of the supply of air admitted to the flue from the heating chambers 5 or in conjunction with such heated air supply.

The electrical heating devices may also be employed for the purpose of increasing the temperature of the gases passing from one heating chamber to another, for instance, in-

flowing past the same.

In either furnace, the gases escape from the uppermost treating chamber by any suitable means, as for instance, by means of a flue 17.

I claim l 1. A furnace having a series of supersaid chambers with one another, and electriposed treating chambers, a flue connecting cal heating devices interposed in said flue between successive chambers of the furnace.

2. A- furnace having a series of treating chambers, air heating chambers interposed between the same, a flue communicating with said treating chambers, and also with the air heating chambers, an electric heating device contained in said flue, and means whereby air on its way to the treating chambers is caused to flow first throughthe interposed heating chambers. and then through the flue containing the electric heating device.

3. A furnace having a series of treating chambers, air heating chambers interposed between the same, a flue communicating with said treating chambers, and also with the air heating chambers, an electric heating device contained in said flue, and means-whereby air on its way to the treating chambers is caused to flow first throughthe interposed heating chambers and then' through the flue centaining'the electric heatin device, the

latter flue also having means or supplying air thereto independently of that derive from the air heatingchamber.

4. A furnace having a flue therein, an

electrical heating device contained in said flue, and a plug carrying said electrical heatapplying the plug to or withdrawing it from the opening in the wall of said flue.

In testimony whereof, I have signed my name to this specification, in thepresence of two subscribing witnesses.

UTLEY WEDGE.

Witnesses KATE A. BEADLE, HAMILTON D. TURNER. 

